Sony's new Android phone, the Xperia Z1S, combines a distinctive design and premium build with stellar stamina and an underwater-capable camera.

When you think of high-end smartphones in the U.S., Sony isn't the first name that comes to mind. However, its new Xperia Z1S -- available exclusively at T-Mobile starting January 22 -- could be the company's strongest effort yet to earn your attention.

Sony Xperia Z1S

On paper, the Z1S looks plenty impressive: The device has a distinctive design, a premium build and all the elements you'd expect in a high-end smartphone today. It also has some unusual standout qualities, like waterproof construction and a 21-megapixel camera that can shoot underwater.

The Xperia Z1S is being sold for a two-year T-Mobile payment plan of $22 per month, bringing its grand unsubsidized total to $528. The phone is available for preorder now.

So how does it all come together -- and what kind of real-world experience does it provide? I've been living with the Xperia Z1S for the past week to find out.

Body and display

One thing's for sure: You won't mistake the Xperia Z1S for any other device in T-Mobile's lineup. Sony's new phone stands out from the pack -- in a good way -- with its flat, squared-off shape and reflective black design. The phone has glass on its front and back and a silver-accented frame around its perimeter.

The frame on the Z1S is made of smooth plastic rather than the aluminum used on other Sony Xperia devices -- a move Sony tells me was made at T-Mobile's request -- but it doesn't look at all cheap. The phone is striking and stylish, and gives off a very premium vibe.

Of course, looks aren't everything -- and while the Z1S is a sight to be seen, it isn't exactly comfortable to hold. Thanks to its large horizontal bezels, the device is 5.7 x 2.9 x 0.34 in. and 5.71 ounces, which is on the upper end of the spectrum for a standard-sized smartphone. With the combination of size, shape and the nature of its materials, the Z1S feels a little awkward and unnatural in the hand. It's a stark contrast to the warm and ergonomic (but also less eye-catching) build of a phone like the Moto X.

The Z1S's materials also make it a magnet for fingerprint smudges and assorted lint -- far more so than any other device I've used. The device looks downright filthy every time I take it out of my pocket. That's not necessarily a deal-breaker, by any means, but it's something to keep in mind, especially with a phone whose appearance is otherwise so noteworthy.

The Xperia Z1S has a 5-in. 1080p LCD display. Generally speaking, the screen looks quite good: It's crystal clear with vivid detail and admirable brightness. Compared to other high-end phone displays, however, the Z1S's colors are noticeably less brilliant, and I can't help but thinking it looks just a tad bit washed out. Its viewing angles are also somewhat limited compared to other devices.

You can take the Z1S out in the rain or even into the tub (if you must) and not worry about it getting damaged

Aside from the 3.5mm headphone jack on its top edge, all of the Xperia Z1S's ports are protected by plastic covers -- part of the phone's waterproof construction. The benefit is that you can take the Z1S out in the rain or even into the tub (if you must) and not worry about it getting damaged; I bathed the phone in a pot of water to test it and, true to Sony's claim, it emerged unscathed. The screen won't respond to your fingers while it's underwater, but you can operate the phone's camera by way of a dedicated hardware button (more on that later in the review).

The downside to the waterproofing is that charging the phone is a minor pain, as you have to remove a protective flap every time you want to plug it in. The Z1S doesn't support wireless charging, but it does have a connector for a proprietary Sony charging dock -- so that's at least an option.

The Z1S has a single large speaker grille on its bottom edge. The phone's audio is reasonably loud, though fairly tinny and hollow-sounding. An optimization feature in the phone's settings called ClearAudio+ helps a little but can only do so much.

The Z1S doesn't have a dedicated HDMI-out port, but you can use its micro-USB port along with an MHL adapter to connect the phone to your TV. The device also allows for wireless screen mirroring with TVs that support the Miracast standard.

Under the hood

Sony's Xperia Z1S is an absolute champ when it comes to performance: With a 2.2GHz quad-core Qualcomm Snapdragon 800 processor and 2GB of RAM, the phone has flown through every task I've thrown its way. It's been smooth as butter the entire time I've used it; I've yet to notice a single stutter or slowdown.

The only oddity I've experienced is with the device's touchscreen: On my review unit, the screen is strangely finicky and sometimes registers taps when I'm actually moving my finger, like when I'm scrolling through a Web page or a thread of social media comments. It happens just enough to be annoying but not debilitating.

The Z1S is no slouch when it comes to stamina: With its 3000mAh battery, the phone has been able to get me through full days of moderate to heavy use without ever breaking a sweat. I've consistently gotten a solid three to four hours of mixed-usage screen-on time while ending the day with at least 30% of the battery remaining.

The Xperia Z1S comes with 32GB of internal storage, about 26GB of which is actually available to you after factoring in the operating system and various preinstalled applications. The phone also has a microSD slot that allows you to add up to 64GB of external space.

Call quality has been A-OK on the Z1S for me, though I have found the phone to be a bit awkward to talk on. Its earpiece is located at the very top edge of its face, all the way above the bezel -- so you basically have to tilt the device and hold the top edge against your ear in order to hear clearly. Especially given the size of the device, that's rather unnatural to do.

Data speeds, meanwhile, have been peachy: The phone supports both LTE and HSPA+-level T-Mobile 4G connections. In my area, where HSPA+ is the best option available, I've been getting around 15Mbps downloads with the device.

Cameras

Sony's putting a lot of focus on the Xperia Z1S's camera, proudly touting that the phone uses a 20.7-megapixel shooter along with its special "G Lens" and "Bionz" processing engine. That's a lot of marketing-speak -- so how does the thing actually perform?

In short, pretty darn well; I'd easily rank the Z1S among the top Android camera phones available today. I wouldn't put too much stock in the big megapixel number alone -- all that means is that the camera can capture very large images and, in fact, the Z1S sticks to 8 megapixels by default -- but with all the pieces put together, you've got a respectable setup by smartphone standards.

Images I've captured with the Xperia Z1S have generally had sharp detail, true-to-life colors and a minimal amount of noise in the background. The latter element in particular is a quality many smartphone cameras fail to achieve.

The Z1S has also shown itself to be unusually good at shooting moving objects without adding much motion blur -- another area where most smartphones tend to struggle. And it's held its own more than I expected in low-light conditions: While it can't keep up with the clarity of the HTC One in that department, the phone is able to get reasonably decent-looking shots in extremely dim environments.

The Z1S's pictures aren't perfect: They sometimes err on the side of being a little dull and washed out, and I can occasionally detect visible artifacting around objects' edges if I zoom into an image and study it in full resolution. But most users aren't going to notice that sort of stuff. For casual photo-taking purposes, the Z1S does a commendable job.

A "Background defocus" mode lets you select a focal point for the image and then blur everything behind it.

The phone's camera software also makes things easy: Sony's custom Camera app is simple to use yet jam-packed with options. By default, the app takes photos in a mode called "Superior auto," which makes all the decisions on-the-fly for you to help get the best possible picture. If you prefer to take matters into your own hands, you can switch to several advanced shooting modes with the tap of a button.

The modes range from the silly -- an "AR effect" mode that adds cartoony elements like hats and dinosaurs into your image -- to the legitimately useful, like a "Timeshift burst" mode that captures a bunch of rapid-fire images and then automatically picks the best one from the bunch. There's also a "Background defocus" mode that lets you select a focal point for the image and then blur everything behind it, creating a slick-looking DSLR-like effect.

And last but not least, as I mentioned earlier, the Xperia Z1S can take photos underwater -- a neat trick that works impressively well. All you do is hold the phone's hardware camera button (located on the bottom-right edge of the device) to launch the Camera app, then press the button a second time to snap a picture. You can take underwater videos, too, but you'll have to go into the app's settings beforehand to change the button's function.

The Z1S can record 1080p-quality HD video on both its primary camera and its 2-megapixel front-facing lens.

The software

The Xperia Z1S runs custom Sony software based on Google's Android 4.3 Jelly Bean operating system. Sony has not yet announced if or when it'll upgrade the phone to the more current Android 4.4 KitKat OS. (You can track the phone's upgrade status via my Android 4.4 upgrade list; as soon as there's any confirmed information about the device's progress, it'll be added onto that page.)

Sony's take on Android sticks pretty close to the core Google software in concept but introduces a fair amount of visual change. Some of the changes are relatively minor, like arbitrarily altered icons or a re-skinned system settings section, while others take a more negative toll on the user experience.

For instance, Sony has reworked the home screen in a way that makes it more difficult to place shortcuts where you want them. Instead of icons automatically dropping into the nearest available spot, as they do in stock Android, Sony's setup requires you to place them precisely in a guideline that appears on the screen; if you miss the mark, the icon shoots back to its previous location.

Sony's setup requires you to place icons precisely in a guideline that appears on the screen.

Moving shortcuts out of the app drawer and onto the home screen also requires an extra step, for no apparent reason, and folders have been altered in a way that makes them both more cumbersome to manage and less attractive to view. Most of the system apps have also been given a custom coat of paint to no great effect -- a classic example of change for the sake of change.

In the big picture, though, these software sins really aren't that bad. Sony's take on Android is quite usable and far more palatable than the heavy-handed efforts most other manufacturers produce. And the fact that the company sticks with the standard on-screen Android navigation buttons goes a long way in making the phone pleasant to use.

To its credit, Sony has added a couple of potentially useful features into the mix. The Z1S's Recent Apps section, for instance, has a panel full of widgets that can open as movable windows on top of other content. The widgets are fairly limited in functionality, but you can add any regular widget into the list and turn it into a movable window as well.

Sony has also done away with the standalone Android Quick Settings panel and replaced it with a customizable bar of toggles that sits above the main notification panel. The implementation is tasteful in this context, and the ability to customize the toggles is a welcome touch.

Sony has bundled plenty of its own content services onto the phone, too -- services for purchasing movies, music and apps -- which causes some confusing overlap with the more robust Google equivalents already present on the device. The company has preloaded two different PlayStation apps as well: The curiously separated "PlayStation" and "PlayStation Mobile." The apps aren't anything you couldn't manually install onto any other Android device, but they do come with 10 free games here, which is a nice perk.

The Xperia Z1S also comes with a credit for six movie downloads from Sony's store as well as a 60-day trial of the company's music streaming service.

SonyPrice: $22/month (for a total of $528) over two-year period from T-MobilePros: Striking and distinctive design; premium build quality; waterproof; top-notch performance; excellent battery life; exceptional camera that works underwater; microSD slot for expandable storageCons: Bulky and awkward to hold; display somewhat washed out and with more limited viewing angles than other devices; inconvenient flaps on all ports and slots; ships with dated version of Android and no upgrade guarantee; no wireless charging